1 /*
2 * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 #include <assert.h>
8 #include <auth_common.h>
9 #include <debug.h>
10 #include <errno.h>
11 #include <img_parser_mod.h>
12 #include <limits.h>
13 #include <stdint.h>
14 #include <string.h>
15
16 extern uintptr_t __PARSER_LIB_DESCS_START__;
17 extern uintptr_t __PARSER_LIB_DESCS_END__;
18 #define PARSER_LIB_DESCS_START ((uintptr_t) (&__PARSER_LIB_DESCS_START__))
19 #define PARSER_LIB_DESCS_END ((uintptr_t) (&__PARSER_LIB_DESCS_END__))
20 static unsigned int parser_lib_indices[IMG_MAX_TYPES];
21 static img_parser_lib_desc_t *parser_lib_descs;
22
23 #define INVALID_IDX UINT_MAX
24
validate_desc(img_parser_lib_desc_t * desc)25 static void validate_desc(img_parser_lib_desc_t *desc)
26 {
27 assert(desc != NULL);
28 assert(desc->init != NULL);
29 assert(desc->name != NULL);
30 assert(desc->check_integrity != NULL);
31 assert(desc->get_auth_param != NULL);
32 }
33
img_parser_init(void)34 void img_parser_init(void)
35 {
36 unsigned int index, mod_num;
37
38 /* Initialise internal variables to invalid state */
39 for (index = 0; index < IMG_MAX_TYPES; index++) {
40 parser_lib_indices[index] = INVALID_IDX;
41 }
42
43 /* Calculate how many image parsers are registered. At least one parser
44 * must be present */
45 mod_num = PARSER_LIB_DESCS_END - PARSER_LIB_DESCS_START;
46 mod_num /= sizeof(img_parser_lib_desc_t);
47 assert(mod_num > 0);
48
49 parser_lib_descs = (img_parser_lib_desc_t *) PARSER_LIB_DESCS_START;
50 for (index = 0; index < mod_num; index++) {
51
52 /* Check that the image parser library descriptor is valid */
53 validate_desc(&parser_lib_descs[index]);
54
55 /* Initialize image parser */
56 parser_lib_descs[index].init();
57
58 /* Ensure only one parser is registered for each image type */
59 assert(parser_lib_indices[parser_lib_descs[index].img_type] ==
60 INVALID_IDX);
61
62 /* Keep the index of this hash calculator */
63 parser_lib_indices[parser_lib_descs[index].img_type] = index;
64 }
65 }
66
img_parser_check_integrity(img_type_t img_type,void * img_ptr,unsigned int img_len)67 int img_parser_check_integrity(img_type_t img_type,
68 void *img_ptr, unsigned int img_len)
69 {
70 unsigned int idx;
71
72 assert(img_ptr != NULL);
73 assert(img_len != 0);
74
75 /* No integrity checks on raw images */
76 if (img_type == IMG_RAW) {
77 return IMG_PARSER_OK;
78 }
79
80 /* Find the index of the required image parser */
81 idx = parser_lib_indices[img_type];
82 assert(idx != INVALID_IDX);
83
84 /* Call the function to check the image integrity */
85 return parser_lib_descs[idx].check_integrity(img_ptr, img_len);
86 }
87
88 /*
89 * Extract an authentication parameter from an image
90 *
91 * Parameters:
92 * img_type: image type (certificate, raw image, etc)
93 * type_desc: provides info to obtain the parameter
94 * img_ptr: pointer to image data
95 * img_len: image length
96 * param_ptr: [out] stores a pointer to the parameter
97 * param_len: [out] stores the length of the parameter
98 */
img_parser_get_auth_param(img_type_t img_type,const auth_param_type_desc_t * type_desc,void * img_ptr,unsigned int img_len,void ** param_ptr,unsigned int * param_len)99 int img_parser_get_auth_param(img_type_t img_type,
100 const auth_param_type_desc_t *type_desc,
101 void *img_ptr, unsigned int img_len,
102 void **param_ptr, unsigned int *param_len)
103 {
104 unsigned int idx;
105
106 assert(type_desc != NULL);
107 assert(img_ptr != NULL);
108 assert(img_len != 0);
109 assert(param_ptr != NULL);
110 assert(param_len != NULL);
111
112 /* In a raw image we can only get the data itself */
113 if (img_type == IMG_RAW) {
114 assert(type_desc->type == AUTH_PARAM_RAW_DATA);
115 *param_ptr = img_ptr;
116 *param_len = img_len;
117 return IMG_PARSER_OK;
118 }
119
120 /* Find the index of the required image parser library */
121 idx = parser_lib_indices[img_type];
122 assert(idx != INVALID_IDX);
123
124 /* Call the function to obtain the parameter */
125 return parser_lib_descs[idx].get_auth_param(type_desc, img_ptr, img_len,
126 param_ptr, param_len);
127 }
128